Index: bfblender/source/blender/python/api2_2x/doc/NLA.py
===================================================================
--- bfblender/source/blender/python/api2_2x/doc/NLA.py	(revision 13106)
+++ bfblender/source/blender/python/api2_2x/doc/NLA.py	(working copy)
@@ -18,6 +18,7 @@
 	- HOLD: continue displaying the last frame past the end of the strip
 	- ACTIVE: action strip is active in NLA window
 	- LOCK_ACTION: action start/end are automatically mapped to strip duration
+	- MUTE: action strip does not contribute to the NLA solution
 
 @type StrideAxes: readonly dictionary
 @var StrideAxes: Constant dict used by the L{ActionStrip.strideAxis} attribute.
Index: bfblender/source/blender/python/api2_2x/NLA.c
===================================================================
--- bfblender/source/blender/python/api2_2x/NLA.c	(revision 13106)
+++ bfblender/source/blender/python/api2_2x/NLA.c	(working copy)
@@ -805,7 +805,8 @@
  */
 
 #define ACTIONSTRIP_MASK (ACTSTRIP_SELECT | ACTSTRIP_USESTRIDE \
-		| ACTSTRIP_HOLDLASTFRAME | ACTSTRIP_ACTIVE | ACTSTRIP_LOCK_ACTION)
+		| ACTSTRIP_HOLDLASTFRAME | ACTSTRIP_ACTIVE | ACTSTRIP_LOCK_ACTION \
+		| ACTSTRIP_MUTE)
 
 static PyObject *ActionStrip_getFlag( BPy_ActionStrip * self )
 {
@@ -1181,6 +1182,8 @@
 				PyInt_FromLong( ACTSTRIP_ACTIVE ) );
 		PyConstant_Insert( d, "LOCK_ACTION",
 				PyInt_FromLong( ACTSTRIP_LOCK_ACTION ) );
+		PyConstant_Insert( d, "MUTE",
+				PyInt_FromLong( ACTSTRIP_MUTE ) );
 	}
 	return S;
 }